Moody's Investors Service has lowered the outlook for the credit ratings of three of Europe's strongest economies: Luxembourg, the Netherlands and Germany. It's part of a busy day in Europe that has investors on-edge -- markets there are barely moving.

The credit rating agency Moody's slashed the ratings of 15 of the world's biggest financial institutions, including Citigroup and Bank of America here in the U.S. and Barclays and Credit Suisse in Europe.

Europe correspondent Stephen Beard discusses why the European markets remained pretty steady despite the credit downgrades of several European countries, and why we ought to worry about the Greek debt talks collapsing.